Photochemical 1,2 Shift of the Phosphane Ligands in the Silanediyl Complex [(2-Ph2PCH2C6H4)2Si[double bond]Cr(CO)5]

1 : A solution of 9 [25] (22 mmol) in Et,O (40 mL) was added slowly over 15 min at 0 -C to a solution of phenylsilane (2.4 g, 22 mmol) in Et,O (40 mL). The mixture was stirred at room temperature for 2 h and then hydrolyzed at 0°C with 0.4 mL ofH,O. After filtration on celite. distillation gave 5.4 g (83%) of 1 as a colorless oil. B.p. 115-117 'C/0.02Torr; 'HNMR (250 MHz, CDCI,, TMS):6 = 2.0(s. 12H.CH3),3.51 (S,~H,CH~),~.~~(S,~H,S~H,);~~S~NMR (200 MHz. CDCI,, TMS): 6 = 51.5 (t. 'J(SiH), 200 Hz): IR(CC1,): i.[cm'1 = 21 11 (SiH,). Correct elemental analyses (C.H.N,Si). 2a: A solution ofiodine (0 43 g. 1.67 mmol) in ether (10 mL) was added dropwise to a solution of silane 1 (1 g, 3.35 mmol) in Et,O (10 mL) at room temperature under argon. The resulting mixture was stirred until evolution of H, had ceased It became progressively colorlessas a precipitate appeared. The mixture was then filtered, and the residue washed twice with ether to give 1.4 g (100% yield) of a white microcrystalline powder. M.p. 135°C (decomp); 'HNMR (250 MHz, CD,CI,, TMS). 6 = 2.2 ( s , 6 H , CH,), 2.85 ( s , 6 H , CH,). 4.0 (d, 2J(H,H)=l6Hz,2H,CH2),4.25(d.zJ(H,H)=l6H~,2H.CH,),5.3(s,1H, SiH): "C NMR (200 MHz, CDCI,. TMS): 6 = 63.1 (CH,N), 47.1, 47.6 (N(CH,),). 11-3.2. 124.2, 127.3, 128.8, 131.2, 134.0, 143.0; 29Si NMR (200 MHz. CDCI,, TMS): 6 = 29.7 (d, 'J(Si,H) = 280 Hz); IR(KBr): i. [cm ~ I] = 2202. 2c: A solution of 9 [25] (7.38 mmol) in Et,O (50 mL) was added slowly to a solution of dichlorophenylsilane (1.1 mL. 7.38 mmol) in Et,O (50mL). The mixture was stirred at room temperature for 2 h. After filtration. the solid obtained was dissolved in CH,CI, to precipitate LiCl which was removed by filtration. After concentration. Et,O was added to precipitate crude 2 c as a whlte \olid (1.9 g. 90%) whose characterlstics are the same as those of 2a. 6: A solution of I, (0.4 g. 1.56 mmol) in Et,O (15 mL) was added dropwise at 5 C to asolution ofsilane 5(b.p. = 45-50'C/0.1 Torr)(0.7 g, 3.15 mmol)in Et,O (15 inL). The mixture was stirred at room temperature for 4 h, filtered. and the solid obtained washed twice with Et,O to give 1.1 g (100%) ofcrude 6. M.p. 145 C (decomp); 'HNMR (80 MHz, CDCI,. TMS): 6 = 2.9 (s, 12H. CH,). 4.4 (s. 4 H , CH,), 4.9 (s, 2 H , SiH,); "Si NMR (250 MHz, CDCI,. TMS): d = 46.4 (t, 'J(S1.H) = 265 Hz); IR (KBr): i.[crn-'] = 2191 and 2209.